Treatment of paper



United States Patent TREATMENT OF PAPER Lon Frangois Orsini, Lyon, France, assignor to Societe des Usines Chimiques Rhone-Poulenc, Paris, France,

a corporation of France No Drawing. Application February 28, 1956 Serial No. 568,177

Claims priority, application France April 13, 1955 10'Claims. (Cl. 117-76) This invention relates to a process for improving the resistance of wallpapers to water, staining and washing while avoiding damage either to their appearance or to the stability of their colours.

.In the treatment of wallpapers certainprecautions must be taken since it is essential that the treatment carried out should not alter either the mechanical resistance of the paper or the decorative appearance thereof. The use of organic solvents in the industrial manufacture of wallpapers is frequently inconvenient, the manufacturers usually not being equipped to handle organic solvents, so that it is essential to be able to effect the treatment in the aqueous phase. Furthermore treatment carried out with a view to improving the decorative surface of a wallpaper must not impair the affinity of the other surface with respect to the aqueous adhesives, usually having a starch, dextrin or like base, employed for hanging the paper.

Because of the foregoing difficulties no fully satisfactory result has yet been obtained in the treatment of wallpaper to impart thereto a satisfactory resistance to water and to various kinds of marks or stains on the paper (e. g. caused by solid or liquid fatty substances, ink, sweets or wine), so that after being in use for some time,wallpapers are frequently marked with stains and non-pleasing streaks. It is generally 'not possible to remove such stains by simply rubbing them with a cloth or sp'onge impregnated with solvent of a detergent solution, because the papers themselves, and the colours which are printed thereon, show a low resistance to the rubbing or dissolving action.

According to the present invention a method of treating wallpaper, to impart thereto a resistance to water and to marking, comprises treating the paper with an aqueous solution of aluminium triformate, and then, preferably after drying, with an aqueous emulsion containing an ionic emulsifying agent and an organopolysiloxane in which the ratio of. organic groups (R) to silicon atoms (Si) is from 1 to 2.5. Wallpapers thus treated once they are dried and hung, present an excellent resistance to water and to marking and in addition readily withstand washing.

Preferably the concentration of the aqueous solution.

of aluminium triformate employed is quite low, e. g. 0.5 to 5% and preferably 1 to 3%, the percentages being related to aluminium triformate hydrated with 3 molecules of water. The quantity of aluminium salt deposited on the paper may vary, for example, from 0.1 to 2 grams per square metre of paper.

The organopolysiloxanes employed in aqueous emulsion may be of various types, e. g. organopolysiloxane oils, resins, or gums, employed separately or in association. The term organopolysiloxanes is to be understood as designating both the organopolysiloxanes proper and the organosilicic compounds containing at the same time SiO-Sibonds and SiSi bonds, such as described, for example, in French Patent 1,081,726.

The choice of the most suitable product depends on pasted. It is also possible to impregnate the paper, for

- support after being hung.

2. the paper which is treated and may be decided by simple preliminary test.

Generally speaking, it has been found that in order to obtain the best possible efiect, it is preferable that an amount of organopolysiloxane of the order of 0.5 g. per square metre should be deposited on the paper.

Among ionic emulsifying agents employed for preparing the organopolysiloxane emulsions there are preferably employed the stearates or oleates of an organic base, for example, the oleate or stearate of morpholine or triethanolamine, which are readily decomposed on contact with the aluminium triformate previously deposited on the paper.

With wallpapers of good quality, both with respect to the paper support and the decoration, a treatment as just referred to enables the desired result to be easily obtained. For wallpapers of somewhat inferior quality,

it may happen that the distribution of the organosilicic compound on the paper is not uniform and causes stains or rings on the paper. It has been found that this disadvantage is overcome if, prior to forming the emulsion, the polysiloxane is diluted with an organic solvent, such as, for example, petroleum spirit, white spirit, aromatic hydrocarbons or chlorinated solvents, or if butanol or triethanolamine titanate is added to the emulsion when ready for use, or even by combining these two measures. The solution of aluminium triformate and the polysiloxane emulsion are preferably applied only to the decorative surface, for example, with a roller or spraygun, as this preserves the surface which is adapted to be example, by dipping, by means of two successive treatment liquids and it has surprisingly been found that the unprinted surface still receives the paste during the pasting and that the paper adheres satisfactorily to the It is generally preferred to carry out a drying operation between the treatment with aluminium triformate and the treatment with the polysiloxane compound.

The aluminium triformate may Without disadvantage be incorporated in the priming and printing baths during the manufacture of the wallpaper, this having the advantage of obviating a supplementary operation. The essential feature is that the triformate should be deposited on the decorative layers before coating the paper surface with the polysiloxane emulsion.

Wallpapers treated according to the invention do not differ essentially in appearance from similar papers not so treated; in particular they are free from the shiny appearance possessed by papers treated with compositions having a basis of fish oil or synthetic resins.

As already stated, the resistance of the said papers to water, staining and washing is excellent and the following tests have been used for measuring these resistances:

(a) Resistance to water.--Spray Test ASTM D583- SOT .The scale employed varies from O to 100. The value 0 corresponds to a zero water-proofing and the value to a perfect water-proofing.

(b) Resistance to stains.-This test corresponds under working conditions to the deposition of a deep stain on the paper (for example of ink). It consists in depositing a blot of ink on the paper to be examined. After being in contact for one minute, the ink which is not absorbed is removed by means of blotting paper and the wallpaper is rubbed with a sponge soaked in water containing a detergent or a solvent until the stain disappears, the operation being stopped as soon as the paper or the colours are changed. The appearance of the paper at this moment is noted: whether stained or not.

(0) Resistance to washing.Thistest is designed to measure the resistance of the paper, and of the colours which are applied thereto, to repeated washing with water. It consists in rubbing the wallpaper under examination with a sponge soaked in water until there is a change in the paper. The number of times the sponge is moved over the paper until this stage is reached is then noted. This number obviously bears a relationship to the mechanical resistance of the paper and the fastness of the colours applied thereto. Values of 60 or more are considered to be good.

The invention is illustrated by the following examples which however are not to be regarded .as limiting it in any way; the parts, unless otherwise indicated, are by weight; when parts by volume are referred to, the relationship thereof to the parts by. weight is in the ratio of litres to kilograms.

Example I Two samples of good quality wallpapers are impregnated by means of a roller, successively with a-solution of 26 g./litre of aluminium triformate calculated as the crystalline product having 3 molecules of water, and then, after drying for 30 minutes, with a methyl polysiloxane emulsion obtained by dispersing 500 parts of methyl polysiloxane oil with a viscosity of 300 cst. at 25 in 500 parts of water with the aid of parts of morpholine oleate; this emulsion is diluted with water at the time of use in order to bring it to a concentration of 12.5 g. per litre. The treated papers are exposed to air until dry.

It is found that the appearance of the samples is not modified by the treatmentyafter treatment, they havea resistance to water of 90 and a resistance to washing of 90 to 115; they are unstained in the staining resistance test. Samples of the same papers when untreated have a zero resistance to water and a resistance to washing in the region 2 to 5; they are stained in the staining resistance test.

Samples of medium quality paper treated as set out above have the same degrees of resistance to water, staining and washing as the previous papers. However the treatment according to the invention causes the appearance on their surface of a certain number of stains or rings which render them unsuitable for use.

Example [I A methyl polysiloxane oil emulsion is prepared in the following manner:

350 parts of methyl polysiloxane oil having a viscosity of 350 cst. at 25 are diluted with the same weight of petroleum spirit, boiling range 93 to 114 C., and the whole is emulsified in 300 parts of water by means of parts of morpholine oleate. 175 parts of this emulsion are diluted with 400 parts of water. 425 parts of an aqueous solution containing 60 parts of triethanolamine titanate are added to the diluted emulsion thus obtained. By this means, there are obtained 1000 parts of an emulsion containing 6% of methylpolysiloxane and the same percentage of triethanolamine titanate.

Eight samples of wallpaper with a wide range of qualities are impregnated first of all with an aqueous solution of aluminium triformate as in Example I, then dried for 30 minutes at ordinary temperature, and then impregnated with the emulsion of methylpolysiloxanes prepared in the manner just described.

After being dried, all the samples have the same appearance as before treatment and in particular are free from any staining; the resistance to water is between 80 and 90 and the resistance to washing between 90 and 170; they are all unstained as the result of the staining resistance test.

The samples, when pasted on the unprinted side with a dextrin paste and applied to a support, adhere to the latter in a satisfactory manner.

Example III A methylsilicic resin is used which has a CH /Si ratio 4 equal to 1.5 and contains -Si-O-Sibonds and Si-Si bonds.

700 parts by volume of a 50% by weight solution of the said resin in a petroleum spirit, boiling range 93 to 114 C., are emulsified in 300 parts of water by means of morpholine stearate. The emulsion is diluted to a concentration of 6% of resin and the same percentage of triethanolamine titanate is added.

Eight samples of the same wallpapers are treated according to the method described in Example II. The appearance and the degrees of resistance of the treated papers are the same as in Example II.

Example IV An emulsion of methylpolysiloxane oil and resin is used which is obtained in the following manner:

A mixture of 500 parts of methylpolysiloxane resin with a CI-I /Si ratio of 1.5 as a 70% solution in toluene, 333 parts of methylpolysiloxane oil with a viscosity of 300 cst. at 25, and parts of petroleum spirit, boiling range 93 to 114 C., is emulsified in 266 parts of water with the aid of 20 parts of oleic acid and 6.6 parts of morpholine. The emulsion, which contains 55.7% of organosilicic product, is diluted to 35% by the addition of water.

A solution of parts of triethanolamine titanate in 1520 .parts of water is added to 360 parts of the 35% strength emulsion. In this way, there is obtained an emulsion containing 6.3% of organosilicic compounds and 6% of triethanolamine titanate.

By treating two samples of wallpaper with this emulsion according to the method set out in Examples II and III, papers are obtained which have an appearance and degrees of resistance to water, washing and staining similar to those found in the said two examples.

I claim:

1. A method of treating wallpaper to impart thereto a resistance to water and to marking which comprises reating the said paper with an aqueous solution of aluminium triformate and then with an aqueous emulsion containing an ionic emulsifying agent and an organopolysiloxane in which the ratio of organic groups to silicon atoms is from 1 to 2.5.

2. A method of treating wallpaper to impart thereto a resistance to water and to marking which comprises treating the said paper with an aqueous solution of aluminium triformate, drying the said paper and then treating it with an aqueous emulsion containing an ionic emulsifying agent and an organopolysilo-xane in which the ratio of organic groups to silicon atoms is from 1 to 2.5.

3. A method of treating wallpaper to impart thereto a resistance to water and to marking which comprises treating the said paper with an 0.5 to 5% by weight aqueous solution of aluminium triformate calculated as trihydrate, drying the paper and then treating it with an aqueous emulsion containing an ionic emulsifying agent and an organopolysiloxane in which the ratio of organic groups to silicon atoms is from 1 to 2.5

4. A method of treating wallpaper to import thereto a resistance to water and to marking which comprises treating the said paper with a 1 to 3% by weight aqueous solution of aluminium triformate calculated as trihydrate, drying the paper and then treating it with an aqueous emulsion containing an ionic emulsifying agent and an organopolysiloxane in which the ratio of organic groups to silicon atoms is from 1 to 2.5

5. A method of treating wallpaper to impart thereto a resistance to water and to marking which comprises treating the said paper with an 0.5 to 5% by weight aqueous solution of aluminium triformate calculated as trihydrate, drying the paper and then treating it with an aqueous emulsion containing an ionic emulsifying agent and an organopolysiloxane in which the ratio of organic groups to silicon atoms is from 1 to 2.5, the quantity of organopolysiloxane being sufiicient to provide a coating of about 0.5 g. per square metre of organopolysiloxane on the paper surface.

6. A method of treating wallpaper to impart thereto a resistance to water and to marking which comprises I treating the said paper with an 0.5 to 5% by weight aqueous solution of aluminium triformate, calculated as trihydrate, drying the paper and then treating it with an aqueous emulsion containing an ionic emulsifying agent which is decomposed by aluminium triformate and an organopolysiloxane in which the ratio of organic groups to silicon atoms is 1 to 2.5.

7. A method of treating wallpaper to impart thereto a resistance to water and to marking which comprises treating the said paper with an 0.5 to 5% by weight aqueous solution of aluminium triformate, calculated as trihydrate, drying the paper and then treating it with an aqueous emulsion containing an ionic emulsifying agent selected from the class consisting of the oleates and stearates of morpholine and triethanolamine, and an organopolysiloxane in which the ratio of organic groups to silicon atoms is 1 to 2.5.

8. A method of treating wallpaper to impart thereto a resistance to water and to marking which comprises treating the said paper with an 0.5 to 5% by weight aqueous solution of aluminium triforrnate, calculated as trihydrate, drying the paper and then treating it with an aqueous emulsion, containing an ionic emulsifying agent, of a solution in an organic solvent of an organopolysiloxane in which the ratio of organic groups to silicon atoms is 1 to 2.5.

9. A method of treating wallpaper to impart thereto a resistance to water and to marking which comprises treating the said paper with an 0.5 to 5% by weight aqueous solution of aluminium triformate, calculated as trihydrate, drying the paper and then treating it with an aqueous emulsion containing an ionic emulsifying agent, an organO- polysiloxane in which the ratio of organic groups to silicon atoms is 1 to 2.5, and triethanolamine titanate in. a proportion of 20 to by weight of the organopolysiloxane.

10. A method for the production of printed wallpaper having a high resistance to water and to marking which comprises applying to the paper, as a constituent of a priming bath, an aqueous solution of aluminium triformate and thereafter treating the printed paper with an aqueous emulsion containing an ionic emulsifying agent and an organopolysiloxane in which the ratio of organic groups to silicon atoms is from 1 to 2.5.

References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES Burnand, TeinteX, vol. 4 (1939), pages 585-8. Abstracted in Chem. Abstracts, vol. 34, page 2183 

1. A METHOD OF TREATING WALLPAPER TO IMPART THERETO A RESISTANCE TO WATER AND TO MARKING WHICH COMPRISES TREATING THE SAID PAPER WITH AN AQUEOUS SOLU ION OF ALUMINIUM TRIFORMATE AND THEN WITH AN AQUEOUS EMULSION CONTAINING AN IONIC EMULSFYING AGENT AND AN ORGANOPOLYSILOXANE IN WHICH THE RATIO OF ORGANIC GROUPS TO SILICON ATOMS IS FROM 1 TO 2.5. 